1. Field of the Invention
The present invention relates to food industry, and, more particularly, to a plant for processing vegetal stock.
2. The Prior Art
Known in the art is a plant for processing vegetal stock comprising a container with bubblers for live steam mounted on a two-wheel trailer with a possibility of angular swivelling, the bubbler being positioned under a net placed wherein in the vegetal stock, which plant incorporates a detachable cover (Information Bulletin of the Crimean MTTSNTI, Issue 1, 1988, Simferopol, "Movable Device for Processing Essential Oil Herb and Flower Raw Material"). The cover is mounted on a vertical guide and communicates through a steam pipe with a cooler inlet chamber which accommodates a steam distributor adapted for distributing steam among a bundle of pipes mounted coaxially in the cooler housing, the cooler communicating through a distillate admission pipe with a separator, which communicates with a tank for collecting the finished product.
This plant is adapted for steaming out essential oil from vegetal stock. As compared to the other prior art plants for processing essential oil, herb and flower raw material, it features simple structure, low metal consumption, and requires less power. Due to the use of the trailer, the loading of the stock is performed directly in the field, which facilitates the yield of high-quality finished product, since the stock gets into the container without any contaminating substances. This plant helps dispense with complicated, costly equipment.
However, the structural arrangement of the container in this plant with the bubblers for live steam positioned under the net in one row fails to provide uniform distribution of the steam along the entire cross section of the container. Moreover, steam escapes from the bubblers' perforations with variable head in the beginning and the end. The live steam at a high pressure and temperature permeates the vegetal stock and causes decomposition of organic material, cellulose inclusive, the smell of the decomposition products impairing the quality of the essential oil obtained. Therefore, in the container of the structure described, it is not advisable to effect high-velocity steaming out of the oil at a high pressure inside the container and at the outlet therefrom. Besides, steam with essential oil, while getting onto the flow distributor in the cooler, is not uniformly distributed among the bundle of pipes dues to the fact that the distributor is shaped as a spherical perforated baffle, which results in considerable losses of essential oil carried away from the cooler outlet chamber by uncondensed steam. The obtained distillate with oil, passing through the admission pipe to the admission compartment of the separator, divides into two fractions, that is, water and oil, due to the difference in their specific weights. Due to the fact that in the separator utilized in the known plant, the pipe is arranged vertically, the heavy fractions of oil are suspended in the form of a lump which, having accumulated the critical mass, is thrown out as a plug from the pipe, and stirring and mixing the fluid in the settling compartment of the separator, agitates the fluid therein, whereby the oil emulsion is enthralled to a sewage system. All this causes reduction in the amount of the finished product and its quality, which renders the plant disadvantageous. In addition, the structural arrangement of the plant provides but a limited field of its utilization, for instance, to carry out extraction of essential oil and biologically active substances with liquid extracting agents, as is the case with the use of live steam, as well as with dead steam, which necessitates the provision of additional costly equipment of a limited use, whereby the cost and dimension of the plant grow.